Electric motor.



H. L. ZA-BRIS'KIE. ELECTRIC MOTOR.

APPLICATION FILED JULY 15, 1911.

1,084,590. Patented Jan. 13, 1914.

2 BHEETSSHEET l.

A TTORNEY H. L. ZABRISKIE. ELECTRIC MOTOR.

APPLICATION FILED JULY 15, 1911.

Patented Jan. 13, 1914 2 SHEETSBHEET 2.

WITNESSES: lNl/E/V'TOI? i1a7m I M J w l/zmax g A TTORNEY our" TED STATESHENRY I. ZABRISKIE, 0F WESTFIELD, NE

TUBING COMPANY, A CORPORATION OF ELECTRIC MOTOR.

Specification of Letters Patent.

Patented Jan. 13, 1914.

Application filed July 15, 1911. Serial No. 638,613.

To all whom it may concern:

Be it known that I, HENRY L. ZABRISKIE, a citizen of the United States,residing at Westfield, in the county of Union and State of New Jersey,have invented certain new and useful Improvements in Electric Motors, ofwhich the following is a specification, reference being had therein tothe accompanying drawings.

This invention relates to an improvement in controlling devices forsmall motors designed for service where frequent starting and stoppingis required, and its object is to combine such controlling mechanismwitha motor-body so that the structure will be compact and self-containedandall its moving parts, excepting the pulley upon the motor-shaft,shall be protected from injury in transportation and subsequentoperation. One of the chief advantages of such a structure is that allof its parts may be assembled and adjusted independently of the machinewhich it is required to drive, so that its installation may be readilyeffected by any one unskilled in the construction and adjustment ofdynamo electric machines.

In the preferred form, the improvement is embodied in an electric motorof the series alternatingcurrent commutator type and comprising a casingprovided with a plurality of pole pieces each surrounded by afield-magnet coil and between which is disposed the rotary armaturewhose shaft carries externally to said casing the pulley through whichpower is transmitted to the belt connected with the machine to bedriven. The field-magnet coils are each divided into main and auxiliarysections. The controller comprises a plurality of independent series ofcircularly arranged fixed contact-studs, the corresponding studs of eachseries being adapted for connection by an oscillatory controller-armprovided with connected brushes resting upon said contacts. Theauxiliary sections of the field-coils are connected by conductor wiresor taps in such relation that the corresponding sections aresimultaneously thrown into and out of the field circuit by the action ofthe controller-arm.

The contact-points of the controller are arranged in the motor-casingand within the magnetic influence of the pole-pieces which serve toprevent any arcing produced by the action of thecontroller-arm insuccessively making and breaking contact between the oppositecontact-points, and the controllerarm is mounted upon the inner face ofthe end cover of the motor-casing upon whose outer face is fulcrumed abrake-lever carrymg at one end a brake-shoe in operative relation withthe rim of the driving pulley and at the other end a stud normallypressed in contact with a plural-stepped segmental cam carried by thecontroller-arm which latter is attached to a chain or other suitableconnection with means external to the motor-casing for actuating thecontroller, and through it controlling the spring-pressed brake-lever.

The invention will be more fully understood by reference to theaccompanying drawings, in which- Figure 1 is a partial sectional sideelevation of an electric motor provided with the presentimprovements,'-and Fig. 2 an end v ew of the same with the pulley rim insection. Fig. 3 is an end view of the motorcasing with the end cover andthe brake-lever removed. Fig. 4 is a perspective view representing thecontroller and the brakelever detached from the motor-frame, and Fig. 5a similar view showing portions of is a diagram to show the principle ofoperation of the controller.

The 'motor is shown constructed with a casing comprising the main body1,rearward end cover 2 and forward end cover 3', the end covers beingprovided with bearing bosses in which is journaled the motor-shaft 4carrying the armature 5. rotating between the inwardly extendingpole-pieces 6 formed upon the laminated ring 7 secured within thecasing, said pole-pieces being embraced by the sectional field-magnetcoils 8. The motor-casing is shown provided externally with the boss .9to which is secured by means of the screws 10 a foot-piece 11 by whichit is attached to a suitable support in operative relation with themachine to be driven.

The body 1 of the casing is provided internally near the forward endwith lugs 12 to which is secured by means of the screws 13 the annular.plate 14 of fiber or other suitable-insulating material in which aresecured the series of relatively insulated contactstuds 15 16 arrangedin diametrically opposite series, each diametrically opposite pair ofsuch contact-studs being connected to one extremity of correspondingsections of the field-magnet coils 8 by means of the conducthecontroller-arm and the end cap. Fig. 6 i

tor Wires or taps 17 18, 17*- 18, 17 18 and 17 18, respectively, asrepresented dlagrammatically in Fig. 6.

The inner face of the end cover 3 is provided with an inwardly extendingtubular bearing boss 19upon which is mounted the hub 20 of thecontroller-arm 21 which is formed at each of the opposite extremitieswith an aperture 21 containing the insulatin bushing 22 embracing thetubular metallic brush-socket 23 whose other end portion is formed witha slot 24 and has secured thereon a clip 25 whose spaced ears 26 carrythe cross-pin 27 supporting the coilspring 28 having one arm 29 restingupon the inturned lip 30 of the adjacent ear 26 and another arm 31extended laterally through the slot 24 and resting upon the outer end ofthe cylindrical carbon brush 32 disposed within the socket 23 and withits forward end resting upon one of the contact-studs 15 or 16 Whoseinner ends are provided with the clamp-nuts 33 for securing theextremity of the tap leading from its respective section of thefield-coils to the contact-stud. The brush-sockets 23 are permanentlyconnected togetherby means of the insulated wire 34.

The reduced inner portion 19 of the end cover bearing boss 19 hassecured thereto by means of the screw 35 one extremity of the spiralspring 36 whose opposite end is formed with an eye embracing astud-screw 37 projecting from the adjacent face of a lateral extension38 of the controller-arm 21 which is also provided with a pin 39projecting from its outer face and upon which is secured by means of thecross-pin 40 one end-link of the operating chain 41 passing through thelateral aperture 42 of the casing.

The spring 36 serves to normally main- ,tain one end portion of thecontroller-arm in engagement with a stop-lug43 upon the inner face ofthe end cover 3 with its brushes 32 connecting the dead contact points15 and 16*. The drawing down of the chain by a treadle or other meansserves to progressively connect the diametrically oppositecontact-points so as to first throw into the armature circuit the entiremotorfield and then reduce the ,active portion of the same section bysection, until the opposite end portion of the controller-arm engagesthe stop-lug 44 upon the inner face of the end cap 3, when the taps 17and 18 are connected to maintain inthe circuit only the mainfield-coils. By progressively reducing the number of turns of thefieldcoils in the circuit, the speed is varied from a minimum, utilizingall of the field-coils, to a maximum, wherein all of the auxiliarysections are cut out. By disposing the contact-points within themagnetic influence of the field, the sparking and burning whichtact-studs 15 and 16 roller 43 carried by the stud 49 yielding material.

nos asee to this class of controller The controller-arm 21 is shownprovided upon the side opposite the extension 38 with a segmental cam 45formed in its operative edge with a series of indentations or recesses46 corresponding in number with the live contact-studs of each series,andformed at one end with a deeper recess 4? which corresponds inposition with the dead con- Normally pressed in contact with this cam isthe anti-friction projecting through an aperture 50 in the end. cover 3and secured upon the upper arm 51 of the angular brake-lever fulcruin dupon the outer face of the cover 3 by means of the stud-screw 52 andhaving secured to its depending arm 53 by means of the clampplate 54 andscrews or rivets 55, the brake block formed of leather or other suitableSecured upon the outer end of the motor-shaft 4 by means of theset-screw 57 is the hub 58 of the pulley 59 in the form of a hollow drumembracing the brake-lever and the inner face of whose rim is presentedto the operative edge of the brake-block or shoe 56. cThe pulley hub 58is provided with the V-shaped groove 60 to receive the belt by which themotor is connected with the machine to be driven.

The inner edge of the brake-lever arm 51 is formed with an apertureentered by one of the hooked ends of the brake-spring 61 whose otherextremity enters a transverse aperture in the adjusting screw 62 tappedinto the lug 63 upon the outer face of the cover 3 in which it is lockedagainst turning by means of the lock-nut 64. By suitable adjustment ofthe screw 62, the tension of the spring 61 and the effectiveness of thebrake may be determined.

The form of the pulley-wheel represented in the drawings, andcomprisinga rim extending inwardly from the hub, enables it to act as a housing toconceal and protect the brake mechanism for which it affords a shield.As will be readily seen, the pulleywheel cooperates with the cover-plate3, with its openings to receive the stud 49 and other parts, toeffectively close the forward end of the casing so as to exclude dustand dirt from the operative parts. i

It is evident that the openings in the front end cap represented inlthedrawings will perform the function of a portion of the ventilatingapertures provided in practice, which latter do not materially reducethe effectiveness of the substantially closed casing in shielding thecontained parts from disarrangeazent and otherwise protecting them inthe manner described.

The cam-recess 47 affords suflicicnt clearance, when the circuit is openand the motor is at rest, to entirely release the rollerbrake havingmotor-speed and at all speeds.

stud 48 and thus permit the brake-shoe 56 to act upon the pulley-rim 59under the full power of the spring; but as soon as the chain ll is drawndownward in starting the motor, the roller-stud 18 rides up the inclinedside of the pocket or recess 17 and shifts the brake-lever in oppositionto its spring and maintains the same retracted throughout the period ofoperation of the motor. \Vhile the peripheral notches 46 of the cam 45are not sufliciently deep to wholly release the brake-lever and permitthe same to resume operative relation with the pulley, they serve toyieldingly resist the movement of the controller-arm from each pair ofcontact-studs to the next so as to insure the correct register of thebrushes of the controller-arm with the corresponding con tacts for agiven speed of the motor. The brake-lever therefore has a function inaddition to that of arresting the movement of the motor, of insuring theproper register of the movable and fixed members of the controller toinsure a perfect electrical connection of the parts of the motorcontrolled thereby.

Referring more particularly to Fig. 6, it will be observed that thecurrent from the line wire 65 enters and emerges from the armaturethrough the brushes 66 and commutator 67 and passes thencethrough theconnection 68 into one of the field-coils 8 and thence through the otherfield-coil to the other line wire 69. The controller-arm 21 isrepresented diagrammatically as movable bodily intermediate thecontact-studs which it,is designed to connect, being shown in positionto establish connection between the dead contact-studs 15 and 16. Uponthe actuation of the controller-arm, which may be called the connector,connection is established, through the respective contactstuds, betweenthe taps 17 and 18, thereby closing the circuit through the armature andeach entire field-coil. As the connector progresses from station tostation, it successively connects the taps 17 and 18 17 and 18" and 17and 18, thereby cutting out the auxiliary sections whose terminals werepreviously connected and reducing the nun1- ber of turns in the fieldand increasing the speed ofthe motor up to the maximum, the beenmaintained retracted from operative relation with the pulley 59throughout the period of acceleration of the during the motor at itshighest speed as well.

According to the present improvement in its preferred form, bothfield-coils are subdivided correspondingly and means are provided forprogressively cutting out equal sections from each so as to balance thefield to insure uniformity of action of the motor It is evident,however, that the controller may be readily connected with inspection Ian acute angle to pulley-flange whereby a wedge-like or jaintheoperation of a series of resistance coils adapted to be thrown therebyinto and out of the motor circuit for varying the speed of operation ofthe motor.

From the foregoing description it will be observed that each of themovable members employed in controlling the action of the i otor-shaftis mounted upon the removable end cover of the motor casing, so that theremoval of the latter and the pulley fixed upon the motor-shaft adjacentthereto is all that is necessary to effect the removal of such movablecontrolling parts for and repair without removal of the armature ordisturbing any of the electrical connections, the several contact-studsof the controller being sustained by the insulating ring let which issecured within the body of the motor casing, so that they may bepermanently connected with their re spective field-coil sections.

By reference more particularly to Fig. 2, it will be observed that thefulcrum-stud 52 for the brake-lever is disposed intermediate themotor-shaft 4: and the peripheral flange 59 of the pulley, and that thearm 53 of the brake-lever is extended in a direction opposite to that ofrotation of the pulley as represented by the arrow in said figure. Bythis means, the brake-shoe is given a path of movement around thefulcrum-stud 52 at the adjacent portion of the ming action is producedbetween the brake and the pulley-flange which produces an effectivearresting action with a comparatively light spring 61 for forcing'thebrakeshoe into operative relation with the pulleyfiange. Thus therotation of the pulley materially assists the spring in pres-sing thebrake-shoe upon the pulley-flange, which would not be the case if thebrake-lever were extended in the opposite direction from its sustainingfulcrum-stud.

The present improvement is shown in connection with a bipolar-machine,but it is evidently equally applicable to motors having any number ofpoles arranged in pairs, so long as each is provided with field-coilsdivided into the same number of sections and each of such sections isconnected to the corresponding contact of series corresponding in numberwith the pairs of pole-pieces. It is also evident that the presentimprovement is not limited to the specific details of construction andarrangement of parts shown and described herein, but is susceptible ofconsiderable modification in such particulars within the scope of theinvention.

Having thus set forth the nature of the invention, what I claim hereinis:

1. In an electric motor comprising a closed casing and an armatureinclosed therein and rotating in a magnetic field, a controller disposedwithin and protected by the motor said field, a

field within the casing and provided with a series of fixed contactsdisposed within the influence of movable contact member for establishingelectrical connection between said contacts, a brake device forarresting the rotation of said armature, and an operative connectionbetween said brake device and said movable contact member.

2. lnnn electric motor comprising a casingand an armature rotating in amagnetic same, a controller disposed within the motor casing, a pulleydisposed exterior to said casing and driven by the motor, a brakemounted upon the exterior of the motor casing and in operative relationwith said pulley and operatively connected with the controller, andmeans for operating the controller from the exterior of the motorcasing;

3. In an electric motor comprising a plurality of magnetic pole-piecesand a rotary armature intermediate the same, a motorshaft carrying saidarmature, a controller disposed within the motor casing and comprising aplurality of contacts arranged the inotor-shaft and in close proximityto and within the magnetic influence of said pole-pieces, and acontroller arm also arranged within the motor casing and adapted toconnect said contacts, means exterior to said casing for operating saidcontroller-arm, a pulley upon' the motor-shaft, a brake exterior to saidmotor casing and adapted for engagement with said pulley, and anoperative connection between the controller-arm and said brake.

at. In an electric motor comprising a plurality of pole-pieces eachcarrying a sectional field-coil, and a rotary armature in termediatesaid pole-pieces, a controller comprising a plurality of fixed contactsarranged in series corresponding in number with the pole-pieces of themotor and in concentric relation with the armature and a movable contactmember adapted for establishing connection between correspondingcontacts of each series, and a series of tape each connecting one of thefield-coil sections with a contact of its respective series whereby thecontroller may be operated to cut out simultaneously from each motorfield-coil a corresponding section.

5. In an electric motor comprising a closed casing containing twopole-pieces each carrying a sectional field-coil subdivided intosections corresponding with those of the other fieldcoil, and a rotaryarmature intermediate said pole-pieces, a controller inclosed withinsaid casing and comprising two circularly arranged series of fixed livecontacts, those composing each series corresponding in number with thesections of each field-coil, and a controller-arm adapted tosuccessively connect in pairs the contacts of one series with those ofthe other for concentrically with establishing connections between thecorre sponding sections of said field-coils.

6. An electric motor comprising a casing constructed with a body portioncarrying a plurality of magnetic pole-pieces and a removable end coverfor said casing, a motorshaft, an armature mounted upon said shaftintermediate the pole-pieces, a controller disposed within the motorcasing and comprising fixed and movable members, a brake mounted uponthe outer face of the end cover, a pulley secured upon said shaftadjacent the end cover and in operative relation with and embracing saidbrake, an operative connection between the movable member of thecontroller and said brake, and actuating means for the controller andbrake.

7. The combination with an electric motor-frame comprising a bodyportion and a removable end cover therefor, of a controller having aseries of stationary contacts cured within said body portion and a 1novable contact-connecting member mounted upon and sustained by the innerface of said cover, and controller actuating means.

8. The combination with an electric mo tor-frame comprising a bodyportion and a removable end cover therefor, of a controller having aseries of stationary contacts secured within said body portionand amovable contact-connecting member mounted upon and sustained by theinner face of said cover, a brake device mounted upon the outer face ofsaid cover, an operative connection between the movable member of saidcontroller and said brake device, and controller actuating means.

9. An electric motor comprising a casing constructed with a body portioncarrying a plurality of magnetic pole-pieces and a removable end coverfor said casing having an inwardly extending tubular bearing boss, amotor-shaft journaled in said bearing boss, an armature mounted uponsaid shaft intermediate the pole-pieces, a plurality of fixed contactsmounted within the body of the easing, a series of field-coil sectionseach connected with one of said fixed contacts, a controller-armjournaled upon the tubular bearing boss of said end cover of the casingand provided with connected brushes adapted for establishing electricalconnection between said fixed contacts, and means for operating saidcontroller-arm.

10. An electric motor comprising a casing constructed with a bodyportion carrying a plurality of magnetic pole-pieces and a removable endcover for said casing, a motor-shaft, an armature mounted upon saidshaft intermediate the pole-pieces, a plurality of fixed contactsmounted within the body of the casing, a series of field-coil sectionseach connected with one of said fixed contacts, a pivotally mountedconing said pole-pieces and end of the same, a motor-shaft upon whichtroller-arm provided with connected brushes adapted for establishing theelectrical connection between said fixed contacts, a cam carried by saidcontroller-arm and formed with a segmental series of recesses, aspringpressed stud in operative relation with said cam and adapted inconjunction there-with to produce an intermittent resistance to themovement ofsaid controller arm, and actuating means for saidcontroller-arm.

11. An electric-motor comprising a plurality of magnetic pole-pieces anda rotary armature intermediate the same, a motorcasing composed of abody portion embraca cover closing one the armature is mounted, aplurality of fixed contacts arranged concentrically withthe-motor-shaft, a series of field-coil sections each connected withoneof said fixed contacts, a controller-arm mounted concentrically withsaid shaft at the inner face of said cover and adapted for establishingelectrical connection between said fixed contact-s, a hollowpulley fixedupon said shaft adjacent said cover with its rim in close proximity tothe latter, a brake-lever mounted upon the outer face of said coverandcarrying a shoe adapted for engagement with the inner face of thepulley-rim, an operative connection extending through said cover betweenthe brake-lever and controller-arm, and means exterior to said casingfor actuating the controller-arm.

12. The combination with an electric motor comprising a frameconstructed with a body portion and a removable end cover therefor and amotor-shaft, of a pulley mounted upon said shaft external to the endcover and having an annular flange extending toward the latter, abrake-lever fulcrumed upon said end cover intermediate the motor-shaftand the pulley-flange and extending in a direction opposite to that ofrotation of said pulley and carrying a shoe adapted for engagement withthe inner face of said pulley-flange, and actuating means for saidbrake-lever.-

13. In an electric-motor comprising a closed casing, a plurality ofmagnetic polepieces, a rotary armature intermediate the same, and amotor-shaft carrying said'armature, a controller disposed within themotor-casing and comprising a plurality of fixed'contacts arrangedconcentrically with the motor-shaft and in close proximity to and withinthe magnetic influence of said pole-pieces, a movable controller memberalso'arranged within the motor casing and adapted to engage and connectsaid contacts, and means exterior to said casing for operating thecontroller member.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses.

HENRY L. ZABRI SKIE.

Witnesses:

HENRY A. KORNEMANN, W. P. STEWART.

